Sectional water-tube boiler



JaLn. 24,1928. 1,657,266 a. MAAS SECTIONAL WATER TUBE BOILER Filed Sept.13, 1926 0' Fi .3 w ""9 g a v 71' v 2 i T 1! t l a 5 d (I A z 4 PatentedJan. 24, 1928.

UNITED STATES 1,5512% PATENT OFFICE.

GEORG MAAS, F NUREMBERG, GERMANY.

SECTIONAL WATER-TUBE BOILER.

Application filed September 13, 1926, Serial No. 135,196, and in GermanyJune 15, 1925.

This invention relates to certain new and useful improvements insectional water tube boilers and has for its primary object to constructa boiler with the tube banks set low into the furnace structure with thewater and steam headers or chambers, and connecting pipes therefor, sodisposed as to permit unobstructed upward removal of the tube banks forrepair or other purposes.

An embodiment of the invention is shown by way of example, in theaccompanying drawing, in which Fig. 1 shows in elevation a single boilerheated on one side with a maximum eificiency bank of water tubesconnected without inter mediate element to the unheated steam collectingdrum.

Fig. 2 is a plan View of Fig. 1.

Fig. 3 shows in elevation a single boiler heated on one side withconnection of the maximum eiiiciency bank of water tubes to the steamcollecting drum of the same, said connection being arranged above thehighest water level.

Referring to Figs. 1 and 2 a is the most strongly heated, steep maximumefficiency bank of water tubes consisting of a few water tubes, and Z)is the less strongly heated, steep low efficiency bank of water tunescomprising a greater number of tubes. Both banks are connected at thebottom end to a water supply chamber 0 and separated the one from theother for the greatest part of their length by a guide wall (Z for theflue chamber 0. From a feed drum 7, partly filled with water the waterflows to the chamber 0 through a downcomer g. According to the inventionthe tubes of the low efficiency bank I) and at the top in a steamdischarge chamber h, whilst the tubes of the high efliciency bank a passalong side the chamber in and through the roof 2' and directly into anexterior unheated high efiiciency drum is.

A tube Z conducts the steam generated in the low efficiency bank 1) intothe drum f. The water spaces of the drums f, 7c are con nected with oneanother by a pipe m and the steam spaces of the same by the pipes n. Theunited steam is discharged through a pipe 0 connected to the pipes n.Between the bank I) and a guide wall p for the flue gas downwardlydirected from thedrum f a superheater g is arranged. From the furuses7*, arranged at one side, the flue gases.

gaswhich starts from the water supply are conducted in the direction ofthe arrow 8, by means of the guide walls cl and g) and of the transverseguide walls 25 joined to the same, in serpentine lines so that they flowalso along the superheater q, and the waste gases escape, in thecommonly used manner,

in downward direction after having passed again through the lowefliciency bank of water tubes.

The pipes m, n, 0 and the drums is, f are arranged, according to theinvention, at the outer side of the space which is required for removingthe tubes of the low efficiency bank in upward direction. By thisarrangement the great advantage is obtained, that, as these tubes can beremoved in upward direction, the boiler plant can be very low, owing tothe fact that the large space which had, up to the present time, to beprovided under the chamber for the downward removal of the lowefficiency bank of water tubes, is no longer necessary.

The drum is as shown in Fig. 3 is mounted at such high distance abovethe drum 7, thatthe tubes of the maximum efficiency bank a extend evenabove the highest water level in the feed drum f so that their endsremain dry and form their own evaporation surface. In this manner thefree discharging of the steam from the tubes is still further improved.The water tubes, connecting the drums f and 72 can be omitted in thiscase.

I claim A sectional water tube boiler comprising in combination, a moststrongly heated steep high efficiency bank of water tubes cons1st-. ingof a few tubes only, a less strongly heated steep low efficiency bank ofwater tubes consisting of a greater number of water tubes, a watersupply chamber to which the bottom ends of the water tubes of said twobanks are connected, a guide wall for the flue gas upwardly extendingfrom said water supply chamber and separating said two banks, the onefrom the other on the greatest part of their length, a steam dischargechamber into which the top ends of the water tubes of said lowefliciency bank end, a feed drum partly filled with water, a downcomerconnecting said feed drum to said water supply chamber, a highefficiency, steam collecting drum to which the upper ends of the watertubes of the high efiiciency bank are connected, a pipe connecting theWater space of said high efliciency drum to the water space of said feeddrum, pipes connecting the steam space of said high ef ficiency drum tothe steam space of said feed drum, and a steam discharge pipe connectedto said connecting pipe for the steam spaces of the high eificiency drumand of the feed drum, and said connecting pipes for the water and steamspaces of the high efliciency :drum and forthe feed drum, the steamdischarge pipes, and the high eflieiency drum and the feed drum being sodisposed to pi'esent an unobstructed pathway above the low efiiciencybank of tubes to 1)(3I- mit removal in an upward direction of the Watertubes of the low efficiency bank of Water tubes.

In testimony whereof I afiix my signature.

GEORG Mme.

